sequence determination

Sequence determination in geology, known as stratigraphy, involves describing rock layers and placing them in a time scale. Geologists use principles like the law of superposition, which states that in undisturbed layers, the oldest are at the bottom and the youngest are at the top. This helps establish a relative chronology.1234

To determine absolute ages, geologists use methods like radiometric dating, which measures radioactive decay. Fossils are also crucial for dating, as different geological periods have unique fossil assemblages, a principle known as faunal succession. By correlating rock layers across different locations using these methods, geologists reconstruct Earth's history.4563